Apparatus and process for removing chips from blind holes

ABSTRACT

An apparatus for removing chips from a blind hole has a blowpipe which is projected into the hole so that when high pressure air is discharged from the blowpipe, the chips in the hole are dislodged and propelled toward the open end of the hole. The apparatus further has a contractable bellows, the end of which bears against the workpiece in surrounding relation to the hole. The bellows leads to a container in which the chips are collected and a vacuum is induced in the container by a venturi arrangement or other suitable device so as to create an airstream which conveys the dislodged chips through the bellows and to the container.

United States Patent 1191 Weimer APPARATUS AND PROCESS FOR REMOVING CHIPS FROM BLIND HOLES [76} Inventor: Gerald A. Weimer, 214 Peeke Ave,

Kirkwood, Mo. 63122 [221 Filed: Nov. 19, 1973 21 Appl. No.:416,8l0

[ 1 Aug. 5, 1975 Primary E.mnziner-Edward L. Roberts Attorney, Agent, or Firm-Gravely, Lieder & Woodruff [57] ABSTRACT An apparatus for removing chips from a blind hole has a blowpipe which is projected into the hole so that when high pressure air is discharged from the blowpipe, the chips in the hole are dislodged and propelled toward the open end of the hole. The apparatus further has a contractable bellows. the end of which bears against the workpiece in surrounding relation to the hole. The bellows leads to a container in which the chips are collected and a vacuum is induced in the container by a venturi arrangement or other suitable device so as to create an airstream which conveys the dislodged chips through the bellows and to the container.

13 Claims, 5 Drawing Figures APPARATUS AND PROCESS FOR REMOVING CHIPS FROM BLIND HOLES BACKGROUND OF THE INVENTION This invention relates in general to forming holes in workpieces, and more particularly to an apparatus and process for removing chips from such holes.

Usually drilling blind holes in workpieces or otherwise finishing those holes, such as by tapping or reaming, results in an accumulation of chips at the bottoms of the holes. The usual procedure for removing the chips is to direct a blast of air from an air gun into the hole so as to in effect blow the chips out of the hole. This, however, is a dangerous practice for the chips are propelled a high velocity and can become lodged in ones skin or much worse ones eyes. To minimize this hazard, many operators of such devices wrap shop towels around the air gun, and this has the effect of deflecting the chips away from the eyes and hands. Indeed, some of the chips are deflected directly back into the hole while others are directed over the surrounding area from which they must be removed. This in many instances presents a sizeable cleaning problem in itself.

SUMMARY OF THE INVENTION One of the principal objects of the present invention is to provide a tool for removing chips from blind holes and for simultaneously collecting the chips so removed. Another object is to provide a tool of the type stated which simultaneously directs a blast of high pressure air toward the closed end of a blind hole and induces a par tial vacuum at the open end. A further object is to provide a tool of the type stated which removes chips from blind holes without hazard to the operator. An additional object is to provide a tool of the type stated which is simple in construction and highly reliable. Still another object is to provide a process for easily, safely, and quickly removing chips from blind holes and for collecting such chips. These and other objects and advantages will become apparent hereinafter.

The present invention is embodied in an apparatus for removing particles from holes and includes a blow pipe which is inserted into the hole to dislodge particles therefrom and means for collecting the particles so dislodged. It also includes a process wherein the chips dislodged are conveyed away from the hole in an airstream and are collected. The invention also consists in the parts and in the arrangements and combinations of parts hereinafter described and claimed.

DESCRIPTION OF THE DRAWINGS In the accompanying drawings which form part of the specification and wherein like numerals and letters refer to like parts hwerever they occur:

FIG. I is a perspective view of a chip removing tool constructed in accordance with and embodying the present invention;

FIG. 2 is a sectional view in elevation of the chip removing tool; and

FIGS. 3, 4 and are sectional views taken along lines 33, 44 and 5-5 of FIG. 2, respectively.

DETAILED DESCRIPTION Referring now to the drawings (FIG. 1), A designates an apparatus or tool for removing chips or other debris from a blind hole 11 in a workpiece W. The tool A is connected to a high pressure air hose b by means of a suitable connector. When actuated. the tool A directs a blast or jet of high pressure air toward the bottom of the hole I: from within the hole 11 and simultaneously induces a partial vacuum at the open end so that any chips in the hole h are dislodged and withdrawn therefrom.

The tool A includes (FIG. 2) a base or body 2 having a chip receiving container 4 connected to the underside thereof by means of a threaded connector 6 which is affixed firmly to the underside of the body 2. The container 4 is preferably molded from a transparent plastic so that its contents can be observed. and its upper rim bears against a gasket to completely seal its interior along the threads which attack it to the body 2. Extending completely through the body 2 is a main bore 8. one end of which is threaded for connection to an air valve l0 having an operating handle [2 for actuating the same. The air valve 10 is connected to the high pressure air hose b and when the handle 12 is depressed. allows high pressure air to flow from the hose b into the main bore 8 of the body 2.

The opposite end of the bore 8 is somewhat enlarged and has a sleeve 14 press-fitted into it (FIG. 2). The sleeve 14 projects beyond the body 2 where it is received in the end of a tubular bellows 16, being secured thereto by a hose clamp IS. The bellows 16 is formed from a suitable elastomer and is of circular cross section. Both ends of the bellows 6 are reduced and intermediate these ends the bellows 16 is corrugated. The bellows 16 projects a substantial distance beyond the body 2 when unrestrained. but due to its corrugated configuration it is easily collapsed. that is contracted in the axial direction, so that its far end may be brought closer to the body 2. The corrugations. however. provide the bellows 16 with substantial strength in the radial direction so that it does not easily collapse in that direction. The reduced end located remote from the body 2 has an abutment sleeve 20 fitted therein and this sleeve is formed from steel or some other rigid material. The sleeve 20 projects beyond the end of the bellows I6 where it is provided with a series ofcircumferentially spaced vent apertures 22. The sleeve 20 has guide collars 24 (FIG. 5) supported therein on radial arms 26 with the collars 24 being coaxial with the sleeve 20. The radial arms 26 should be as narrow as possible so as not to impede the passage of chips through the sleeve 20 and into the bellows 16.

Turning again to the bore 8 (FIG. 2) in the body 2, the intermediate portion of the bore 8 is about the same in diameter as the threaded end in which the valve 10 is retained and this portion is connected with the threaded end through a throat 28. The intermediate portion has a bushing 30 fitted snugly in it, and this bushing is sealed against the wall of the bore 8 by an O- ring 32. The O-ring 32 is actually at the rear end of the bushing 30, which is the end located adjacent to the throat 28, and the reduction in the diameter of the bore 8 at this point prevents the bushing 30 from moving further toward the air valve 10. Withdrawal ofthe bushing 30 in the opposite direction is prevented by a set screw 34 which is threaded into the body 2 and tightened down against the forward end of the bushing 30. Hence, the bushing 30 is secured firmly in the intermediate portion of the bore and is further sealed against the wall of the bore 8 so that all air passing through the intermediate portion of the bore 8 must flow through the center of the bushing 30. The throat 28 and the portion of the bore 8 located adjacent the valve 10 constitute a supply passage.

Press-fitted or otherwise secured tightly in the bushing 30 is a blowpipe 36 (FIG. 2) which extends axially through the bore 8 and the bellows 16 as well as through the guide collars 24 in the sleeve 20 at the end of the bellows 16. Indeed. the end of the blowpipe 36 is disposed beyond the sleeve 20 even when the bellows 16 is unrestrained and expanded to its fullest length. The guide collars 24 in the sleeve 20 ride on the surface of the pipe 36 as the bellows l6 contracts, and they maintain the bellows 16 generally centered about the pipe 36. The outer diameter of the pipe 36 is considerably smaller than the inner diameters of the abutment sleeve 20, the bellows 16, the sleeve 14 and the adjoining portion of the main bore 8 so that an annular collecting passage 38 is created about the pipe 36. The free end of the pipe 36 is cut oblique to the axial center line for the pipe 36 to prevent the end edge of the pipe 36 from being pressed and sealed against a flat surface, such as the base of the blind hole h.

That portion of the main bore 8 which extends between the bushing 30 and the sleeve 14 communicates with a discharge tube 42 (FIG. 2) fitted tightly into the body 2 and extended downwardly into the container 4 where it terminates. The tube 42 and the portion of the bore 8 with which it communicates constitute a return passage.

On the other hand, that portion of the main bore 8 located between the throat 28 and the air valve I0 is intersected by a venturi passage 44 (FIGS. 2-4) which is in effect four different bores in the body 2. the last of which is a bore 46 (FIG. 3) extended generally through the center of the body 2 beneath the main bore 8 and at right angles thereto. The last bore 46 of the venturi passageway 44 is fitted with a venturi nozzle 48 which projects into a venturi cavity in the form of an enlarged transverse bore 50 extended all the way to the external side surface of the body 2. The terminal end of the transverse bore 50 is filled with steel wool 52 or some other porous material which reduces the noise of air issuing from the venturi nozzle 48. The steel wool 52 is held in the bore 52 by a screen covered retainer plate 54 secured against the side surface of the body 2.

The transverse bore 50 communicates with a vacuum tube 56 (FIGS. 2 and 4) which extends downwardly into the container 4 adjacent to discharge tube 42 with the axial center line of the tube 42 intersecting the axial center line of the transverse bore 50 at right angles. The tip of the venturi nozzle 48 projects out to but not further than the axial center line of the vacuum tube 56. That portion of the tube 56 which is within the container 4 is provided with apertures 58 and is encased in a tubular filter material 60 which may be cloth.

OPERATION To remove chips from the blind hole h, the free end of the blowpipe 36 is inserted into the open end of the hole h in the workpiece W (FIG. 1), and the entire tool A is advanced toward the workpiece until the oblique end of the blowpipe 36 bottoms out against the closed end of the hole h. As the blow-pipe 36 advances through the hole h, the abutment sleeve 20 at the end of the bellows 16 seats against the workpiece W and the corrugated portion of the bellows l6 contracts. Nevertheless, the guide collars 24 maintain the sleeve 20 and bellows l6 centered about the blowpipe 36 so that the annular collecting passage 38 between the blowpipe 36 and the bellows I6 is not restricted.

Once the free end of the blowpipe 36 bottoms out against the base of the hole h, the operating handle 12 of the valve I0 is depressed and the valve 10 admits high pressure air to the main bore 8 of the body 2. Most of the air flows into the throat 28 and then into the blowpipe 36, at relatively high velocity. The high velocity air issuing from the obliquely cut free end of the pipe 36 dislodges chips from the base and walls of the blind hole It and propels them toward the open end of the hole 11. Indeed, the velocity imparted to the chips propels them directly into the bellows nozzle 20 and thence into the interior of the annular collecting passage 38 within the bellows l6.

While most of the high pressure air admitted to the main bore 8 enters the blowpipe 36, some of it flows into the venturi passageway 44, from which it is discharged through venturi nozzle 48 at high velocity. The high velocity of the air issuing from the venturi nozzle 48 has a venturi effect, that is it induces a partial vacuum in the surrounding portion of the transverse bore and the vacuum tube 56. The reduction in pressure in the vacuum tube 56 causes air to enter the tool A at the abutment sleeve 20 and flow through the bellows l6, sleeve 14, main bore 8, and discharge tube 42 to the container 4. The air leaves the container 4 through the vacuum tube 56 and transverse bore 50. Any chips dislodged by the blast of air from the blowpipe 36 will become entrained in the airstream flowing through the bellows l6 and will be carried into the container 4 in the airstream. Due to the fact that the container 4 is much greater in cross-sectional area than the annular collecting passage 38 and discharge tube 42, the airstream loses velocity in the container 4 and drops the chips entrained therein to the bottom of the container 4. The filter material prevents the chips from entering the vacuum tube 56.

From the foregoing, it is quite apparent that the tool A dislodges chips from blind holes I: with considerable force, yet completely confines those chips to the interior of the tool A so that they cannot harm the operator or other individuals standing nearby. Moreover, the tool A collects the chips so that subsequent clean-up is unnecessary.

The partial vacuum created in the container 4 by the high velocity air issuing from the venturi nozzle 48, may be induced by a completely independent device, such as a vacuum pump, in which case the venturi passageway 44 and nozzle 48 would not be necessary. Also, instead of being hand-held and operated, the tool A or a similar device may be mounted on a machine for automated operation.

This invention is intended to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure which do not constitute departures from the spirit and scope of the invention.

What is claimed is:

l. A tool for removing material from a hole in a workpiece, said tool comprising: a base containing a supply passage connected to a source of high pressure air and a return passage having an inlet end and an outlet end, the base also having a venturi cavity and an apertured vacuum tube in communication with the venturi cavity, the base further having a venturi nozzle directed into the venturi cavity and connected with the supply passage so that air is discharged at high velocity from the nozzle into the venturi cavity and creates a partial vacuum in the venturi cavity and the vacuum tube; a rigid container attached to the body and enclos ing the vacuum tube and the outlet end of the return passage, the container being considerably larger in cross-section than the vacuum tube and further being sealed to the base so that the vacuum is also induced in the interior of the container and in the return passage: a blowpipe projected from the base through the inlet end of the return passage; a bellows surrounding the blowpipe and being collapsible in the axial direction, one end of the bellows being secured to the body at the inlet end of the return passage so that the vacuum will also exist in the bellows; a guide encircling the blowpipe for a short axial distance and being attached to the other end of the bellows to position said other end generally concentrically with respect to the blowpipe irrespective of the axial position of said other end along the blowpipe, whereby when the blowpipe is inserted into the hole the bellows will contract and when air is introduced into the supply passage it passes through the blowpipe to dislodge material in the hole with the material so dislodged being conveyed through the bellows and the return passage to the container where it is collected.

2. A tool according to claim 1 wherein the vacuum tube has apertures in its sidewall, and further comprising a filter material surrounding the vacuum tube and covering the apertures therein.

3. A tool according to claim 1 wherein the guide comprises at least one collar encircling the blowpipe and being movable axially thereon, a sleeve connected securely to the other end of said bellows, and arms connecting the collar and sleeve and maintaining the sleeve generally concentric with respect to the collar and blowpipe.

4. A tool according to claim 3 wherein the sleeve has vent apertures to vent the interior thereof to the surrounding atmosphere.

S. A tool according to claim 1 wherein the blowpipe has a bushing attached firmly to its one end and the bushing is received in the supply passage of the base; and wherein the base is further provided with a set screw which screws down against the bushing and secures the bushing and blowpipe in the base.

6. A tool according to claim 1 wherein the base also has a discharge tube projecting therefrom and into the container parallel to the vacuum tube, and the return passage extends through the discharge tube.

7. A tool for removing material from a hole in a workpiece, said tool comprising: a body having supply passage and a return passage with the return passage having an inlet end and an outlet end, both of which open out of the body; a valve connected to a source of high pressure air and to the supply passage for admitting high pressure air to the supply passage when actuated; a blowpipe secured to and projecting beyond the body, the blowpipe at its one end being connected with the supply passage so that high pressure air admitted to the supply passage enters the blowpipe and is discharged therefrom, the blowpipe projecting through the inlet end of the return passage; a rigid and impervious collection container sealed to the body and enclosing the outlet and of the return passage; venturi means in the body and connected with the supply passage for inducing a partial vacuum in the container and the re turn passage when high pressure air is admitted to the supply passage; a bellows connected to the body and enclosing the inlet end of the return passage thereon so that the vacuum is also induced in the return passage, the bellows encircling the blowpipe and being collapsible in the axial direction so that the distance the blowpipe projects beyond the bellows can be varied; and guide means at the opposite end of the bellows for maintaining the blowpipe generally centered with respect to said opposite end of the bellows as the bellows expands and contracts.

8. A tool according to claim 7 wherein the guide means comprises at least one collar fitted around the blowpipe so that it may move axially thereon. a sleeve fitted into said opposite end of the bellows, and arms extended between the collar and sleeve to maintain the sleeve concentric about the collar.

9. A tool according to claim 8 wherein the sleeve projects beyond said opposite end of the bellows for abutment against the workpiece around the hole in the workpiece; and wherein the portion of the sleeve located beyond the bellows is provided with apertures which vent the interior of the sleeve to the surrounding atmospherev 10. A tool according to claim 7 wherein the venturi means comprises a bore having one end vented to the atmosphere and along its side being in communication with the interior of the container, and a nozzle in the body and directed axially into the bore from the opposite end thereof, the nozzle being connected with the supply passage so that high pressure air will flow through the nozzle and into the bore and induce a partial vacuum in the bore.

11. A tool according to claim 10 wherein the bore beyond the nozzle is filled with a porous material to reduce the noise of air issuing from the nozzle.

12. A tool according to claim 10 and further comprising a vacuum tube attached to the body and having its interior in communication with the bore along the side of the bore, the tube having at least one opening which is covered with a filter material.

[3. A tool for removing material from a hole in a workpiece, said tool comprising a body having supply passage and a return passage with the return passage having an inlet end and an outlet end, both of which open out of the body; a valve connected to a source of high pressure air and to the supply passage for admitting high pressure air to the supply passage when actuated; a blowpipe secured to and projecting beyond the body, the blowpipe at its one end being connected with the supply passage so that high pressure air admitted to the supply passage enters the blowpipe and is discharged therefrom. the blowpipe projecting through the inlet end of the return passage; a rigid and impervious collection container sealed to the body and enclosing the outlet end of the return passage; vacuum means connected with the container for inducing a partial vacuum in the container and return passage; a bellows connected to the body and enclosing the inlet end of the return passage thereon, the bellows encircling the blowpipe and being collapsible in the axial direction, so that the distance the blowpipe projects beyond the bellows can be varied; and guide means at the opposite end of the bellows for maintaining the blowpipe generally centered with respect to the opposite end of the bellows as the bellows expands and contracts, the guide means including a sleeve which is connected to the opposite end of the bellows and has a foward margin positioned to abut against the workpiece around the hole therein when the blowpipe is inserted into the hole, the sleeve having apertures therein adjacent its forward margin for venting the interior of the sleeve to the surrounding atmosphere. 

1. A tool for removing material from a hole in a workpiece, said tool comprising: a base containing a supply passage connected to a source of high pressure air and a return passage having an inlet end and an outlet end, the base also having a venturi cavity and an apertured vacuum tube in communication with the venturi cavity, the base further having a venturi nozzle directed into the venturi cavity and connected with the supply passage so that air is discharged at high velocity from the nozzle into the venturi cavity and creates a partial vacuum in the venturi cavity and the vacuum tube; a rigid container attached to the body and enclosing the vacuum tube and the outlet end of the return passage, the container being considerably larger in cross-section than the vacuum tube and further being sealed to the base so that the vacuum is also induced in the interior of the container and in the return passage; a blowpipe projected from the base through the inlet end of the return passage; a bellows surrounding the blowpipe and being collapsible in the axial direction, one end of the bellows being secured to the body at the inlet end of the return passage so that the vacuum will also exist in the bellows; a guide encircling the blowpipe for a short axial distance and being attached to the other end of the bellows to position said other end generally concentrically with respect to the blowpipe irrespective of the axial position of said other end along the blowpipe, whereby when the blowpipe is inserted into the hole the bellows will contract and when air is introduced into the suPply passage it passes through the blowpipe to dislodge material in the hole with the material so dislodged being conveyed through the bellows and the return passage to the container where it is collected.
 2. A tool according to claim 1 wherein the vacuum tube has apertures in its sidewall, and further comprising a filter material surrounding the vacuum tube and covering the apertures therein.
 3. A tool according to claim 1 wherein the guide comprises at least one collar encircling the blowpipe and being movable axially thereon, a sleeve connected securely to the other end of said bellows, and arms connecting the collar and sleeve and maintaining the sleeve generally concentric with respect to the collar and blowpipe.
 4. A tool according to claim 3 wherein the sleeve has vent apertures to vent the interior thereof to the surrounding atmosphere.
 5. A tool according to claim 1 wherein the blowpipe has a bushing attached firmly to its one end and the bushing is received in the supply passage of the base; and wherein the base is further provided with a set screw which screws down against the bushing and secures the bushing and blowpipe in the base.
 6. A tool according to claim 1 wherein the base also has a discharge tube projecting therefrom and into the container parallel to the vacuum tube, and the return passage extends through the discharge tube.
 7. A tool for removing material from a hole in a workpiece, said tool comprising: a body having supply passage and a return passage with the return passage having an inlet end and an outlet end, both of which open out of the body; a valve connected to a source of high pressure air and to the supply passage for admitting high pressure air to the supply passage when actuated; a blowpipe secured to and projecting beyond the body, the blowpipe at its one end being connected with the supply passage so that high pressure air admitted to the supply passage enters the blowpipe and is discharged therefrom, the blowpipe projecting through the inlet end of the return passage; a rigid and impervious collection container sealed to the body and enclosing the outlet and of the return passage; venturi means in the body and connected with the supply passage for inducing a partial vacuum in the container and the return passage when high pressure air is admitted to the supply passage; a bellows connected to the body and enclosing the inlet end of the return passage thereon so that the vacuum is also induced in the return passage, the bellows encircling the blowpipe and being collapsible in the axial direction so that the distance the blowpipe projects beyond the bellows can be varied; and guide means at the opposite end of the bellows for maintaining the blowpipe generally centered with respect to said opposite end of the bellows as the bellows expands and contracts.
 8. A tool according to claim 7 wherein the guide means comprises at least one collar fitted around the blowpipe so that it may move axially thereon, a sleeve fitted into said opposite end of the bellows, and arms extended between the collar and sleeve to maintain the sleeve concentric about the collar.
 9. A tool according to claim 8 wherein the sleeve projects beyond said opposite end of the bellows for abutment against the workpiece around the hole in the workpiece; and wherein the portion of the sleeve located beyond the bellows is provided with apertures which vent the interior of the sleeve to the surrounding atmosphere.
 10. A tool according to claim 7 wherein the venturi means comprises a bore having one end vented to the atmosphere and along its side being in communication with the interior of the container, and a nozzle in the body and directed axially into the bore from the opposite end thereof, the nozzle being connected with the supply passage so that high pressure air will flow through the nozzle and into the bore and induce a partial vacuum in the bore.
 11. A tool according to claim 10 wherein the bore beyond the nozzle is filled with a porous matErial to reduce the noise of air issuing from the nozzle.
 12. A tool according to claim 10 and further comprising a vacuum tube attached to the body and having its interior in communication with the bore along the side of the bore, the tube having at least one opening which is covered with a filter material.
 13. A tool for removing material from a hole in a workpiece, said tool comprising a body having supply passage and a return passage with the return passage having an inlet end and an outlet end, both of which open out of the body; a valve connected to a source of high pressure air and to the supply passage for admitting high pressure air to the supply passage when actuated; a blowpipe secured to and projecting beyond the body, the blowpipe at its one end being connected with the supply passage so that high pressure air admitted to the supply passage enters the blowpipe and is discharged therefrom, the blowpipe projecting through the inlet end of the return passage; a rigid and impervious collection container sealed to the body and enclosing the outlet end of the return passage; vacuum means connected with the container for inducing a partial vacuum in the container and return passage; a bellows connected to the body and enclosing the inlet end of the return passage thereon, the bellows encircling the blowpipe and being collapsible in the axial direction, so that the distance the blowpipe projects beyond the bellows can be varied; and guide means at the opposite end of the bellows for maintaining the blowpipe generally centered with respect to the opposite end of the bellows as the bellows expands and contracts, the guide means including a sleeve which is connected to the opposite end of the bellows and has a foward margin positioned to abut against the workpiece around the hole therein when the blowpipe is inserted into the hole, the sleeve having apertures therein adjacent its forward margin for venting the interior of the sleeve to the surrounding atmosphere. 